Silk vs Bamboo and Eucalyptus 'Silk': What's the Difference?

They aren't silk at all. "Bamboo silk" and "eucalyptus silk" are marketing names for lyocell and viscose — soft, plant-derived fabrics spun from wood pulp, not the protein filament a silkworm makes. They can feel silky and they have genuine merits of their own, but they're a fundamentally different material: real silk is a natural protein, like your own hair; bamboo and eucalyptus "silk" are regenerated cellulose, closer cousins to rayon than to silk. The word "silk" on those labels describes the feel they're aiming for, not what the fabric is. Once you know that, the comparison becomes clear.

Here's what these fabrics actually are, how they really compare to silk, and how to know which you're buying.

Are bamboo silk and eucalyptus silk actually silk?

No — and it's worth being plain about it, because the naming is genuinely confusing. True silk is a protein fiber (fibroin) reeled from the cocoon of the silkworm. "Bamboo silk" and "eucalyptus silk" contain no silk whatsoever; they're plant-based fabrics in which the word "silk" is used loosely to suggest softness and sheen. The same trick happens with "satin", and for the same reason: silk is the gold standard for a smooth, lustrous fabric, so other materials borrow its name. If a label says "bamboo silk", read it as "a silky-feeling bamboo-derived fabric", not as silk.

What bamboo and eucalyptus "silk" really are

Both are regenerated cellulose — semi-synthetic fabrics made by chemically dissolving plant pulp into a liquid and spinning it back into fiber. Eucalyptus "silk" is almost always lyocell (you'll know the brand name Tencel), made from eucalyptus wood in a relatively closed-loop, lower-impact process. Bamboo "silk" is usually bamboo viscose (a type of rayon), made from bamboo pulp — softer-sounding than it is sustainable, since conventional viscose processing is chemically intensive. Both start as a plant and end as a manufactured fiber. They're legitimate, often lovely fabrics — but they're manufactured cellulose, in the same family as rayon and modal, and a world away from a silkworm's thread.

How they compare to real silk

The differences that matter come straight from what each fabric is made of:

• What it is: silk is a natural protein (akin to hair and skin); bamboo and eucalyptus "silk" are plant cellulose, regenerated into fiber.
• Moisture: lyocell and viscose are absorbent, and so is silk. Silk is often said to absorb less than cotton. Standard textile tables say otherwise: moisture regain is about 11% for silk and about 8.5% for cotton. So absorbency isn't a reason to choose between them.
• For hair and skin: silk is prized for its smooth surface, which means less friction. Many people find that means fewer tangles and less frizz, and you may wake with fewer sleep creases. The plant "silks" can be smooth too, and we know of no good study comparing them with silk on a pillow.
• Temperature: silk is breathable and can feel cool at first touch, though it doesn't regulate temperature; lyocell is breathable too, while bamboo viscose varies by quality.
• Feel and luster: good lyocell is beautifully soft with a subtle sheen; silk has a deeper, shifting luster that's hard to fully imitate.

Are they better or worse than silk?

Honestly, it depends what you want — they're not simply "fake silk to avoid". Lyocell in particular is a genuinely good fabric: soft, breathable, vegan, and (in its closed-loop form) relatively eco-friendly, often at a lower price than silk. If you want a plant-based, animal-free, budget-conscious smooth fabric, eucalyptus lyocell is a fair choice on its own terms. What it doesn't give you is the specific thing people buy silk for: a natural protein fiber with silk's feel and luster. And bamboo viscose's "natural and sustainable" marketing deserves a skeptical eye — the bamboo plant is renewable, but turning it into viscose usually isn't the green process the label implies. So: good fabrics, yes; the same as silk, no.

How to tell what you're actually buying

Ignore the romantic name and read the fiber content, which by law has to be stated. Real silk will say "100% silk" or "100% mulberry silk", ideally with a momme weight; the plant "silks" will list "lyocell", "Tencel", "viscose", "rayon", "bamboo viscose" or "modal" somewhere on the label. Price is a tell too — genuine silk costs more than regenerated cellulose. The same skepticism that helps you spot polyester "satin" applies here; our guide to telling real silk from fake and the difference between silk and satin both go deeper on reading what a fabric truly is.

If it's genuine silk you're after, the protein fiber itself, our LS Silk US mulberry silk pillowcases are 22-momme, made from 100% mulberry silk certified to OEKO-TEX® STANDARD 100, with no marketing-name asterisk.

So "bamboo silk" and "eucalyptus silk" aren't villains — they're decent plant-based fabrics wearing a borrowed name. Just buy them knowing what they are: soft, manufactured cellulose, not the silkworm's thread. When the label has to add a plant to the word "silk", that plant is the real fiber — and silk is the flattery.